280 THE' WOODLANDS. 



pearance in Devon was first observed in 1848 and 

 1849 > m Somerset in 1854; in Gloucester, west of 

 the Severn, in 1855; east of the Severn in 1856; 

 Worcester, 1857 ; in the neighbourhood of London, 

 1858; in North Wales, 1859; Sussex, 1860; Alice 

 Holt Forest, 1861 ; and Cirencester in 1862. At the 

 present time they may be regarded as almost as 

 common as acorns all over the kingdom. It was 

 prognosticated at the time that if these galls were per- 

 mitted to spread they would entirely eradicate the 

 oak from the country. Undoubtedly this gall has 

 long been known upon the Continent, as there is an 

 excellent figure of it in RoseFs work on insects, which 

 is dated 1750. The insect which produces it is 

 a pretty little fat-bodied fly, which may be easily 

 obtained by collecting a quantity of the galls and 

 keeping them in a wide-mouthed bottle until the 

 insects escape. They belong to the same genus, 

 Cynips^ as do so many other of the gall-flies. 



BALANIFORM GALLS are produced on the twigs of 

 the common oak in this country, and on the Conti- 

 nent by a little fly, or Cynipsf and were so called by 

 Mr. Curtis because they somewhat resembled the bar- 

 nacles (Balani) found attached to oyster-shells. They 

 grow in dense masses, or clusters, surrounding the 

 smaller branches, especially near the base ; each gall 

 is somewhat conical with an obtuse apex, and when 

 cut transversely will be found to consist of a single 

 chamber, or cell, containing the larva of the fly. We 

 have met with similar galls on the branches of other 



1 Cynips Kolleri. 2 Cynips corticalis. 



